In the nineteenth century, while the European novel was becoming the preeminent narrative form for grown-ups working through the grown-up problems of marriage, adultery, and career, Americans were writing adventure stories for boys. The classic plot featured a white man — or boy, or man-boy — on the run from the “sivilizing” effects of mothers and wives and responsibility, headed straight for the hearts of dark forests and the open arms of a dark-skinned man. Natty Bumppo had his Chingachgook; Ishmael, his Queequeg; and Huck, an older, wiser, tenderer slave named Jim. It’s almost impossible to overstate the importance of Huckleberry…